How to force ASP.NET Web API to return JSON or XML data based on my input?

Question

I try to get the output XML or JSON data based on my input. I used the below WEB API code but not able to exact output.

public string Get(int id) {     if (GlobalConfiguration.Configuration.Formatters.XmlFormatter == null)     {         GlobalConfiguration.Configuration.Formatters.Add(GlobalConfiguration.Configuration.Formatters.XmlFormatter);     }     if (GlobalConfiguration.Configuration.Formatters.JsonFormatter == null)     {         GlobalConfiguration.Configuration.Formatters.Add(GlobalConfiguration.Configuration.Formatters.JsonFormatter);     }     if (id == 1)     {         GlobalConfiguration.Configuration.Formatters.Remove(GlobalConfiguration.Configuration.Formatters.JsonFormatter);                         GlobalConfiguration.Configuration.Formatters.XmlFormatter.UseXmlSerializer = true;                     }     else     {         GlobalConfiguration.Configuration.Formatters.Remove(GlobalConfiguration.Configuration.Formatters.XmlFormatter);         GlobalConfiguration.Configuration.Formatters.JsonFormatter.UseDataContractJsonSerializer = true;     }     return "value"; } 

Answer 1

Add the below code app_start event in global.asax file. In API Url add the query string:

GlobalConfiguration.Configuration.Formatters.JsonFormatter.MediaTypeMappings.Add(     new QueryStringMapping("type", "json", new MediaTypeHeaderValue("application/json")));  GlobalConfiguration.Configuration.Formatters.XmlFormatter.MediaTypeMappings.Add(     new QueryStringMapping("type", "xml", new MediaTypeHeaderValue("application/xml"))); 

e.g.:

for xml : http://localhost:49533/api/?type=xml  for json: http://localhost:49533/api/?type=json 

Answer 2

What you are trying to do will not work in a multi-threaded environment. You cannot add to and remove from the formatters collection on a per-request basis. Here is a better way of accomplishing what you want.

public HttpResponseMessage Get(int id) {     Foo foo = new Foo();     var content = new ObjectContent<Foo>(foo,                     ((id == 1) ? Configuration.Formatters.XmlFormatter :                                 Configuration.Formatters.JsonFormatter));     return new HttpResponseMessage()     {          Content = content     }; }